Aebofoixi



G. ROESSLER.

AEROFOIL.

APPLICATION FILED SEPT. 7, 1915- Patented Aug. 15, 1916.

GEORGE ROESSLER, TOLEDO, OHIl IO.

* AEBOFOIL.

Specification of Letters Patent.

Application filed September 7, 1915. Serial No.- 49,323.

To all whom it may concern:

Be, it known that I, GEORGE RoEssLnR, a citizen of the United States, and a resident of Toledo, in the county of Lucas and State of Ohio, have invented a certain new and useful Aerofoil; and I do hereby declare the following to be a full, clear, and exact description of the invention, slfch as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form a part of this specification.

My invention relates to an aeronautic means which produces, proportionate to its velocity, the maximum force substantially at right angles to the direction of movement of the means. p,

- It has for its object to produce an aeroplane wherein the lift force and the ratio of the lift to the drift forces of the wings may be greatly varied, thereby giving eat vari-' ability in the weight carrying a ility and also giving great variability invelocity and at the same time maintaining maximum efliciency and stability.

By my invention I. have provided a means for controlling the camber of the lower face of the aerofoil. Also, by my invention is provided a means for controlllng the suction above the aerofoil. Also by my invention is provided an aeromodulator which may be controlled so as to vary the negative pressure, as compared to normal pressure, above the aerofoil. Also, by my invention is provided a means whereby the camber of the aerofoil and the aeromodulator may be varied jointly to obtain the desired lift force and the desired ratio of the lift to thedrift forces.

- The invention maybe contained in many forms of aero constructions usable for different purposes, all of which come within the purview fumy claims hereinafter ap pended. vTo show the practicability of my invention I have selected one of such constructions as an example and shall describe it hereinafter.

illustrated in the accompanying drawings.

The construction selected is Figure 1 of the drawings illustrates diagrammatically a biplane in which my "invention is embodied. Fig: 2 illustrates a sectional view taken along the line H indicated in Fig. 1 to show the aerofoil section: Fig 3"illustrates a side view of the aerofoil control. Fig. 4 illustrates diagrammatlcally a frontview of the controlillustrated in Fig. 1. Fig. 5 illustrates the levers which operate to alter the camber and the angle of incidence of the aerofoil and the position of the aeromodulator. Fig. 6 is a sectional view taken on the line y-y indicated in Fig. 5.

\ 1, Fig. 1, is the hullor the fuselage.

2 is the elevator, 3 is the rudder and 4 are the wings or aerofoils of the biplane which is selected for purposes of illustration. The upper plane 10 is connected to the lower plane 11 by suitable struts 12 which form a part of the frame of the aeroplane and are secured relative to the hull or fuselage 1 in the usual way.

The planes are provided with flexible ribs ,15. A web 18 is placed on the under side of the ribs'15. The web may also be placed on both sides of the rib 15. Beams .19, 20 and '21 are located transversely to the ribs 15. The beams 19 and 21 are fixed relative to the hull or fuselage, and are firmly attached, to the struts 12, while the beams 20 are. pivotally connected by means of the hinges 22 to the beams 19. The ribs are located beneath the beams, The beam 19 is so arranged that it will not interfere with the movements of the ribs and will permit curvature of the ribs while the beams 20 are secured to the ribs 15.

25 are also provided which extend to the trailingedges 26 of the planes and are freely movable through the beam 21. The thrust membersare located above the beams 19 and 20. ey are freely movable over-the beams 19. and are fixed to the beams 20. They are Patented Aug. 15, 1916.

Also, the beam 21 is fixed to the rib 15. Thrustv members connected to the "flexible ribs 15 by tension.

members 27. The tension members 27 are connected by means of the brackets 28 to the ends of the ribs 15. The brackets 28 are secured to the tension members 27, while outer ends of the brackets'28 by the pins 29. Rearward thrusts of the thrust members 25 the ribs 15 arepiVotally connected to the trailing edge 26 of the aerofoil and curve it upward so as to increase the reverse curve of the aerofoil, as shown in the dotted dia graniinatic illustration of Fig. 2. k

The point 29 being relatively fixed and the tension member being located above the thrust line, the trailing edge will be curved upward upon a thrust movement of the thrust member, and at the same time that the curvature of the trailing edge is altered the ribs 15 are curved downward forward of the reverse of the trailing edge since the thrust line is located above the ribs, thus increasing the angle of incidence. The ribs 15 and the thrust members 25 being secured to the beams 20, which are pivoted to the beams 19, the thrust members 25 will move over the beams 19 and the ribs 15 will move under the beams 19 while the beams 20 are turned about the pintle of the hinges 22 by the thrust of the thrust members 25 on the upperedge of the beams 20 also causing the ri s 15 to curve downward, thus increasing the curvature. of the ribs forward of the beams 20, thereby increasing the camber. This is performed at the same time that the reverse curve of the trailing edge of the foil is increased in its curvature upward, causing the trailing edge to follow the stream lines of the air flow which are varied by reason of the increase of the angle of incidence of the foil.

The thrust members v25 may be tied by means of links 30 to the ribs 15 to assist in securing curvature of the ribs 15 and consequently of the foil at the portions thereof in advance of the beam 20. The portions of the thrust members 25forward of the beams 20 when the thrust members are pushed rearwardly are raised, whereby the point of connection of the link 30 to the rib 15 is also raised which coacts to lift the portions of the ribs forward of the beams 20 to change the camber of the plane. They as' sist in increasing the curvature of the for ward portion of the plane. I have thus provided a means whereby the camber is altered with the change of the angle of incidence each camber having a value corresponding to the angle of incidence. By my invention I have also provided a means for increasing the lift force by greatly increasing the suction above the plane, that is, by greatly decreasing'the pressure below normal above the plane. At the forward edge of the 'aerofoil I have provided a means which increases the negative pressure above the foil. I have also provided a means for varying the suction or negative pressure above the plane according to the load. In the particular construction shown, the means "is varied according to the change in the angle of incidence of the plane.

The forward part of the aerofoil is provided with an aeromodulator located above the plane of aerofoil. In the construction shown, I have "provided aledge which extends over the aerofoil. It is formed of ribs 31 which-.may form extensions of the ribs 15. The ribs 31 arecurved rearward from the leading edge of the aerofoil substantially along the stream lines. They are also curved downward toward the top of the aerofoil. The ribs 31 terminate somewhat to the rear of the beams 21. They extend over and are secured to the beams 21. The ribs 31 are covered with web 32. Means is provided for flexing the ledge thus formed according to the negative pressure which it is desired to secure. In the construction shown, the ledge may be flexed with the change in the angle of incidence and the camber of the foil to produce, by the joint operation, the maximum lift force. The ribs 31 may be connected to one or more of the elements which produce changes in camber or angle of incidence. In the construction shown, links 33 are connected to the thrust members 25 in such a way that when the thrust members 25 are pushed rearwardly, the ribs 31 are raised. The links are normally inclined forwardly and when the thrust members are pushed rearwardly the ends connected therewith are pushed toward a vertical line passing through the ends of the links connected to the ribs 31. This causes the aeromodulator to correspond, to the stream line as the camber and the angle of incidence of the aerofoil are changed, keeping the structural head resistance minimum and also producmg the maximum rarity above the aerofoil.

I have thus provided means whereby the aeroplane is suspended not only by reason of the pressure beneath, as in aerofoils heretofore known, but also by the increased rarity of the air above the foil, giving to the aerofoil a lift force which is exceedingly large, thus greatly increasing the efliciency of the aeroplane. I have thus provided a means whereby the variations of the lift force and the ratio of the lift and the drift forces may be greatly varied which enables the aeroplane to be manipulated to produce the greatest possible efficiency at variable speeds and variable loads, this being accomplished by variation of the camber and the angle of incidence and the aeromodulator.

The thrust members 25 may be operated in any suitable manner. In the form of the invention illustrated, I have provided a plate 40 which is located on the beam 21. The plate 40 is provided with ears 41 between which are pivoted bell-crank levers the hull or fuselage so as to be operated by the aeronaut. The ends of the cables are connected to a nut i6 which is feathered in a sleeve 47 and is threaded on a shaft i8. A beveled gear wheel I9 is keyed to the shaft. Upon rotation of the bevel gear wheel I9 the nut *6 is made to slide along the sleeve 47. As the'nut i6 is raised or lowered in the sleeve t? the cables -L5 are pulled in one direction or the other so as to change the camber of the aerofoil. The bevel gear 49 is operated by a meshing gear wheel 50 which is mounted on the end of the sleeve I? and may be rotated by means of a hand wheel .51. The sleeve t7 may be also connected to the elevator 2. The sleeve I? may be swiveled to the sleeve 52 whereby the camber of the aerofoil on one side of the hull or fuselage may be altered so as to increase the camber and angle of incidence while. on the other side of the hull or fuselage. the aerofoil may be altered so as to decrease the angle of incidence and the camber. which is especially valuable in turning and in balancing. On the upper end of the sleeve His supported the steering wheel 55 which is provided with a cable 56 that is connected to the rudder 3.- By rotation of the handwheel 55 therudder is varied in its position relative to the center line of the aeroplane. The sleeve 52 may be pivotally supported and the elevator? may be connected by cables 57 to the sleeve t? above and below the sleeve 52. I have thus pro vided a controlling means which controls all of the variable members of the aeroplane. The aeroplane maybe steered and its elevation-altered and the camber and angle thrust members secured to the opposite edge for varyingthe curvature and angle of incidence of the device. and flexible tension members connected to the ends of the thrust members and the ends of the ribs.

2. In an aeronautic device. a pivoted beam. ribs secured to one edge, of the beam.

thrust members secured to the opposite edge for varying the"curvature and angle of incidence of the device. and flexlble tension members connected to ends of the, thrust sion members and the ribs being located on opposite sides of the thrust members.

In an aeronautic device, a ledge, an aeroplane, and means for flexing the ledge and varying the angle of incidence and camber of the plane.

i. In an aeronautic device-, a ledge, an

aeroplane, and means for flexing the ledgeand varying the angle of incidence and camber of the plane and flexing the trailing edge of the plane.

5. In an aeronautic device, an aerofoil and means for varying the camber and the angle of lncldence of the body portion of the aerofoil and the reversed curvature of bers to vary the relation of the ledge to the body of the aerofoil and to vary the camber and the angle of incidence of the body portion of the aerofoil and the reverse curvature of the trailing edge of the aerofoil.

8. In an aeronautio device. an aerofoil having a ledge formed on its forward edge extending in a curved line upward and rearwardly over the aerofoil. thrust members connectedto the ledge and to the body portion of the aerofoil for flexing the. ledge and varying the camber of the body portion of the aerofoil.

9. In an aeronautic device. an aerofoil. a

flexible ledge formed on the forward edge of the aerofoil and extending ina curved surface upward and rearwardly toform a flexible shelf above the forward edge of the aerofoil. and means for flexing the ledge according to the angle of incidence of the body portion of the aerofoil.

10. In an aeronautic device, an aerofoil.

a flexible ledge formed on the forward edge of the aerofoil and extending in curved surfaces upward and rearwardly to form a flexible shelf above the forward edge of the aerofoil. and means for flexing the ledge.

Intestimony whereof. I have hereunto signed my name to this specification.

GEORGE ROESSLER. 

